El Niño

A warm surface current that sometimes flows off the west coast of South
America and results in prolonged increases in sea-surface temperatures along
the coast of Peru and in the equatorial eastern Pacific Ocean. It is believed
to be closely associated with irregular variations in the global weather
system and it occurs approximately every 7 to 11 years. It is called El
Niño (Spanish for "the Christ Child") because it often begins around
Christmas.

The flow of warm water prevents plankton-rich
cold water from the Antarctic rising to the surface off the coasts of Chile
and Peru. As a result, fish don't come to feed and local fishermen make
no catches. The wider consequences of El Niño can be catastrophic.
The current is associated with short=term changes in worldwide climate patterns,
and may cause drought in places such as Australia; flooding and sever winters
in North America; and violent tropical cyclones in the Pacific Ocean. Some
scientists fear that global warming may be making El Niño occur more
frequently.